Non-crystalline saliva-soluble coatings for elastomeric monofilament dental tapes

ABSTRACT

An improved dental tape treated with a substantive coating containing a crystal control substance, wherein said coating is: saliva soluble, substantially crystal-free, with a flaking value of less than about 20 and a release value of about 100.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority from copending U.S. ProvisionalApplication Serial No. 60/263,220, filed 22 Jan. 2001, the disclosure ofwhich is hereby incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The present invention relates to improved dental tapes.Specifically, the improved dental tapes of the present invention containsubstantially crystal-free coatings that: (a) comprise from 20 to 120%by weight of the floss filament, (b) are saliva soluble and (c) exhibita minimum of flaking. Yet these coatings are released in total into theoral cavity during flossing and can contain ingredients such asabrasives that work with the tape to help physically remove biofilmsfrom interproximal and subgingival surfaces, and chemotherapeuticingredients affecting oral health and subsequent systemic diseasescaused or exacerbated by poor oral health. These coatings areparticularly adapted to monofilament dental tapes.

BACKGROUND OF THE INVENTION

[0003] Historically the purpose of dental floss was: (1) to dislodge andremove decomposing food material that accumulated at interproximal andsubgingival surfaces and could not be removed by brushing or rinsing,and (2) to dislodge and remove bacteria, plaque and/or calculus thataccumulated since the previous flossing and/or cleaning.

[0004] The concept of the use of dental floss for cleansinginterproximal spaces appears to have been introduced by Parmly in 1819.Parmly suggested the use of waxed silk to clean teeth of persons subjectto gingival inflammation.

[0005] The role of plaque, now described as subgingival biofilm, in gumdisease is well documented. The need to physically remove subgingivalbiofilms routinely has become an accepted treatment for gum disease.Mechanical removal of subgingival biofilms can be achievedprofessionally through: scaling, planing, prophylaxis and polishing, andindividually by tooth brushing, proxy brushing and flossing.

[0006] While these methods of physically removing subgingival biofilmsfrom tooth surfaces are effective and well accepted; gum diseasecontinues to be prevalent in the adult population, and consequently,improved means for the individual to physically remove subgingivalbiofilms routinely are indicated.

[0007] Furthermore, the spacing between teeth is not uniform and itvaries considerably, not only from one place to another between the samepair of teeth, but also from one pair of teeth to another pair of teeth.The spacing varies in the same individual, among different individuals,and especially in the case of twisted teeth and teeth that havefillings, crowns, etc.

[0008] To accommodate tight spacing and those interproximal contactsthat do not allow multifilament dental floss to be worked between teethwithout fraying, breaking, etc., a vast array of “TEFLON” dental flosseshave been commercialized. These shred-resistant, monofilament tapes aredescribed in detail in the following U.S. Patents, which are herebyincorporated by reference: 3,664,915; 3,953,566; 3,962,153; 4,096,227;4,187,390; 4,256,806; 4,385,093; 4,478,665; 4,776,358; 5,033,488;5,209,251; 5,220,932; 5,518,012; 5,718,251; 5,765,576; and 5,911,228.

[0009] The TEFLON-type tapes available commercially in the marketplacetoday, include: Gore's Glide®, Oral-B's Satin Floss®, Johnson &Johnson's Easy Slide®, and Colgate's Totals). All of these tapes can beworked between tight spaces with a minimum of fraying and breaking. Yet,unlike their multifilament counterparts such as Johnson & Johnson'swoven floss, REACH® Gentle Gum Care, during flossing, these tapes do notrelease substantial quantities of cleaners, abrasives, tartar controlingredients, whiteners and active ingredients such as fluoride,antimicrobials, antibiotics, etc. The net of this shortcoming in failingto deliver substantial quantities of ingredients to those sites beingflossed is that the tapes are generally perceived as most convenient infitting between teeth, but unfortunately, they are generally perceivedas: “not cleaning”, “not working”, “not doing much”, etc., once they arepositioned between teeth.

[0010] When substantial quantities of cleaning, conditioning andtreating substances are coated onto tapes, the resultant tapes arecharacterized by excessive flaking and breaking off of these coatingsduring processing, dispensing and wrapping of tape around the fingers.As a result, there are no commercial tapes available with substantialcoatings of releasable ingredients suitable for working into andphysically removing biofilms from interproximal and subgingival spaces.

[0011] Biofilms are notorious throughout nature for being difficult toremove. Working a monofilament tape over biofilms in the absence ofsubstantial quantities of cleaners, abrasives, etc., is not effective inphysically removing and/or disrupting substantial quantities ofbiofilms. The net is, critical biofilm buildup interproximally andsubgingivally cannot be effectively physically removed with routineflossing with current commercial dental tapes, both PTFE tapes andbicomponent tapes.

[0012] Monofilament interproximal devices are described and claimed in:U.S. Pat. Nos. Re 35,439; 3,800,812; 4,974,615; 5,760,117; 5,433,226;5,479,952; 5,503,842; 5,755,243; 5,845,652; 5,884,639; 5,918,609;5,962,572; 5,998,431; 6,003,525; 6,083,208; 6,148,830; 6,161,555; and6,027,592, the disclosures of which are hereby incorporated herein byreference. These dental tapes generally have serious shortcomings ingentleness, in delivering coatings during flossing and in being handledeasily and conveniently during flossing

[0013] Polytetrafluoroethylene (PTFE) based interproximal devices aredescribed in: U.S. Pat. Nos. 5,209,251; 5,033,488; 5,518,012; 5,911,228;5,220,932; 4,776,358; 5,718,251; 5,848,600; 5,787,758; and 5,765,576. Todate, no commercial versions of these tapes have been coated effectivelyand cannot be used to deliver active ingredients, interproximally andsubgingivally during flossing. Handling during flossing is difficult.Most have to provide a consumer acceptable edge. Many are plagued withserious dimensional inconsistency problems, as well.

[0014] Several Patent Applications have been filed on monofilamentdental tapes with coatings comprising from between about 20% by weightand about 120% by weight of the monofilament tape. These are describedin copending U.S. Provisional Patent Application Serial Nos. 60/227,433and 60/227,255, filed 23 Aug. 2000 and Serial No. 60/263,220, filed 22Jan. 2001, all of which are hereby incorporated by reference.

[0015] There is clearly a need for a commercial, shred-resistant tapethat is coated with releasable ingredients that help disrupt and/orphysically remove biofilms from critical interproximal and subgingivalsites when used regularly, and deliver chemotherapeutic agents asrequired in a site-specific manner.

SUMMARY OF THE INVENTION

[0016] The present invention centers around the observation that thesubstantivity of coatings onto flexible surfaces, including dentaltapes, can be enhanced such that during flexure of the surface, theseenhanced coatings remain substantive to said surface and resistcracking, fracturing and flaking off. Specifically, it has been observedthat most coated flexible surfaces, especially those formulated to besaliva-soluble and carry effective quantities of abrasives, cleaners,surfactants, and chemotherapeutic agents, fracture along crystal facesduring flexure, thereafter releasing the ingredients from the flexiblesurface by cracking, chipping, flaking and/or falling off etc. Inresponse to these observations, it has been unexpectedly found that theaddition of certain substances to various coatings at relatively modestlevels reduces crystal formation while simultaneously enhancing thecoating's substantivity to flexible surfaces subjected to flexure, whichproperties thereby impart outstanding flake resistance and release valueto said tape.

[0017] Those coating additives that reduce, control and/or eliminatecrystal formation and enhance the substantivity of the coating toflexible surfaces when added to these coatings at modest levels includecertain aliphatic, long chain, fatty alcohols having from between about10 and 30 carbon atoms and/or various liquid surfactants such aspolyethylene glycol sorbitan dialiphatic esters.

[0018] Suitable aliphatic, long chain, fatty alcohols for thecrystal-free coatings of the present invention can be represented by thestructural formula ROH, wherein R represents a long chain alkyl grouphaving from 20 to 30 carbon atoms. Specific examples include: 1-decanol1-heptadecanol 1-pentacosanol 1-undecanol 1-octadecanol 1-hexacosanol1-dodecanol 1-nonadecanol 1-heptacosanol 1-tetradecanol 1-eicosanol1-octacosanol 1-pentadecanol 1-heneicosanol 1-nonacosanol 1-hexadecanol1-tricosanol 1-triacontasol 1-tetracosanol

[0019] Naturally occurring mixtures with substantial quantifies of thesefatty alcohols, or isomers thereof; including those chemically derivedfrom natural sources also constitute suitable sources of aliphatic, longchain fatty alcohols for the purpose of this invention.

[0020] The long chain fatty alcohols can be represented by thestructural formula ROH wherein R represents a long chain alkyl grouphaving from 10 to 30 carbon atoms. These can be purchased commerciallyfrom Stepan, Proctor & Gamble and Aldrich Chemical Co. and a variety ofcompanies processing vegetable and animal derived fatty alcohols.

[0021] Suitable liquid surfactants for the crystal-free coatings of thepresent invention include polyoxyethylene glycol sorbitan mono anddi-aliphatic esters represented by the general formula:

[0022] wherein R₁, R₂, R₃, R₄ are H or aliphatic acyl groups from (10 to30) and the sum of w, x, y, and z is from between 20 and 8O. Theseliquid surfactants are available under the trade names Emsorb®, Span®,Tween® from Cognis N.A. and ICI. Specific examples of these include:

[0023] PEG 20 sorbitan monooleate (Tween® 80, ICI);

[0024] PEG 40 sorbitan monostearate (Span 60®, ICI); and

[0025] PEG 40 sorbitan diisostearate (Emsorb® 2726, Cognis, N.A.).

[0026] Similar esterified, PEG-based surfactants, which are known tothose having ordinary skilled in the art, are also suitable liquidsurfactants.

[0027] One preferred embodiment of this invention thus comprisessubstantive coatings for flexible surfaces that, under flexure, resistcracking, flaking, breaking off, etc.

[0028] Another preferred embodiment of the present invention comprises ashred-resistant dental tape that physically removes biofilms frominterproximal and subgingival sites.

[0029] Another preferred embodiment of the invention comprises a methodof applying substantive coatings of biofilm disrupting substances toshred-resistant tapes which coatings are released onto and worked intobiofilms during flossing.

[0030] A further preferred embodiment of the invention comprisesshred-resistant tapes with substantive coatings that exhibit minimumflaking, yet achieve total release during flossing.

[0031] Yet another preferred embodiment of the invention comprisesmonofilament tapes with substantially crystal-free coatings that aresubstantive, saliva soluble and exhibit with a minimum of flaking.

[0032] Still another preferred embodiment of the invention comprises ashred-resistant dental tape with a substantive coating that helpsphysically remove biofilms when released from the tape during flossing.

[0033] A further preferred embodiment of the present invention comprisessubstantive coatings for dental tapes that contain biofilm disruptingand physically removing ingredients along with biologically active orchemotherapeutic ingredients, all of which are largely or totallyreleased during flossing.

[0034] Still another preferred embodiment of the present inventioncomprises a method for treating interproximal and subgingival sites toremove subgingival and interproximal biofilms while treating said siteswith active ingredients.

[0035] Yet another preferred embodiment of the invention comprises amethod for manufacturing a shred-resistant dental tape that containssubstantial levels of biofilm disrupting/removing ingredients that donot flake off; yet are totally releasable during flossing.

[0036] An other preferred embodiment of the invention comprises coateddental tapes with a flaking value of less than about 20.

[0037] A further preferred embodiment of the invention comprises a classof coated dental tapes with coating release values approaching about100.

[0038] These and other embodiments of the invention are described indetail below.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] For the purposes of the present invention, “crystal-free” isdefined as a smooth surface as distinguished from rough surface typicalof crystalline coatings when observed through a 30× stereo zoommicroscope.

[0040] For the purposes of the present invention, flaking resistancemeasures the propensity of the coatings of the present invention toflake off a flexible elastomeric, TEFLON®, bicomponent, or otherpolymeric dental tapes during flexure. Flaking resistance is based onthe reduction by weight of the crystal-free coating alter flexing, undersuitably controlled and reproducible conditions, an 18-inch piece of thecoated tape for 30 seconds.

[0041] For the purposes of the present invention, release value ismeasured after 18-inches of the tape is thoroughly flossed for 60seconds. The percent of the crystal-free coating removed from the tapeduring flossing establishes the release value.

[0042] For the purposes of the present invention, dental tape is definedas monofilament tapes including elastomeric tapes such as Perident'sFibaclean™, PTFE tapes, such as Gore's Glide®, J&J's Easy Slide® andColgate's Total® and bicomponent tapes such as Oral-B's Satin Tape®.

[0043] Certain petroleum waxes are suitable and preferred additionaladditives for the crystal-free coating of the present invention. Theseinclude any of a range of relatively high molecular weight hydrocarbons(approximately C₁₆ to C₅₀), solid at room temperature, derived from thehigher-boiling petroleum fractions. There are three basic categories ofpetroleum wax: paraffin (crystalline), microcrystalline, and petroleum.Paraffin waxes are produced from the lighter lube oil distillates,generally by chilling the oil and filtering the crystallized wax theyhave a melting point range between 48° C. (118° F.) and 71° C. (160°F.), Fully refined paraffin waxes are dry, hard, and capable ofimparting good gloss. Microcrystalline waxes are produced from heavierlube distillates arid residue (one bottoms) usually by a combination ofsolvent dilution and chilling. They differ from paraffin waxes in havingpoorly defined crystalline structure, darer color, higher viscosity, andhigher melting points—ranging from 63° C. (148° F.) to 93° C. (200° F.).The microcrystalline grades also vary much more widely than paraffins intheir physical characteristics: some are ductile and others are brittleor crumble easily.

[0044] Petrolatum is derived from heavy residual lube stock by propanedilution and filtering or centrifuging. It is microcrystalline incharacter and semi-solid at room temperature. There are also heaviergrades for industrial applications, such as corrosion preventives,carbon paper, and butcher's wrap. Traditionally, the terms slack wax,scale wax and refined wax were used to indicate limitations on oilcontent. Today, these classifications are less exact in their meanings,especially in the distinction between slack wax and scale wax. Naturalwaxes such as beeswax and carnauba wax are also suitable and may providespecifically desired properties.

[0045] Suitable additional ingredients in the crystal-free coating ofthe present invention include anti-plaque ingredients˜such as MICRODENT®and ULTRAMULSION™ as described in various U.S. Patents to Hill, et al.,including U.S. Pat. Nos. 4,911,927; 4,950,479; 5,032,387; 5,098,711;5,165,913; 5,538,667; 5,561,959; 5,66,374 and 5,733,529. The foregoingare incorporated herein by reference.

[0046] Various other active ingredients can be included in thesubstantive saliva-soluble coatings applied to the various dental tapesof the present invention including antimicrobial, anti-tartar,whitening, cleaning, desensitizing, antibiotic, anti-inflammatory,anti-gingivitis ingredients, as well as prostaglandin (PGE₂) andC-reactive protein control substances.

[0047] Specific active ingredients suitable for use in the coated dentaltape of the present invention include: fluoride, potassium nitrate,triclosan, chlorhexidine, cetylpyridinium chlorhexidine, domaphenbromide, metronidazole, doxycycline, aspirin, the essential oils inListerine®, and mixtures thereof.

[0048] The substantial coatings for the dental tapes of the presentinvention can be further characterized as: (a) containing a crystalcontrol substance, (b) being saliva soluble, (c) substantiallycrystal-free, and (d) comprising from between about 20% and 120% byweight of said tape, and having a flake value of less than about 20 anda release value of about 100.

[0049] Elastomeric dental tapes such as described in the referencedco-pending applications coated with the crystal-free coatings of thepresent invention are described in Table I below. TABLE 1 EXAMPLE 1 2 34 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Ingredient Ultramulsion 10-2.557.1 54.8 52.3 50.8 50.8 50.8 58.8 60.8 60.1 55.1 51.1 60.1 61.1 61.153.1 57.1 POLOXAMER 407 60.1 60.1 Emsorb 2726 12.5 7.5 12.5 9 5 3 3 0 33 3 3 3 3 4 3 3 3 Stearyl Alcohol 9.2 10.5 8 7 11 13 15 16 15 15 15 1515 15 10 8 15 15 Insoluble Saccharin 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.81.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 Propyl gallate 0.1 0.1 0.1 0.1 0.10.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Spicemint Flavor 4 44 4 4 4 4 4 5 5 5 5 5 5 5 5 5 5 Vanilla Mint Flavor 4 4 4 4 4 4 4 4 5 55 5 5 5 5 5 5 5 tetrasodiumpyro- 8 14 14 10 10 10 10 10 10 10 14 4 6 610 6 phosphate Dicalcium 10 6 10 phosphate Microcrystalline 10 10 10 0 00 0 5 5 0 7 10 7 7 Wax ML 445 Triclosan 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3Observation Need heat to wind y n y y n y Y y y y y y y y y y Bobbintack 1 5 5 3 4 4 3 2 4 4 3 3 4 3 4 4 (1 = poor, 5 = good) Flakeresistance Feels sticky 5 4 4 2 1 2 2 3 3 3 1 4 3 4 4 (1 = no, 5 = very)Load of two 29/19 Na Na 43/50 28/11 53/39 58/43 33/20 51/40 33 46/5340/39 38/38 50/37 48 45 38/39 43/39 samples Release Value 98 97 100 96100 99 100 100 96 99 98 100 97 99 100 96 100 100

[0050] The present invention has been described in detail, including thepreferred embodiments thereof. However, it will be appreciated thatthose skilled in the art, upon consideration of the present disclosure,may make modifications and/or improvements on this invention and stillbe within the scope and spirit of this invention as set forth in thefollowing claims.

What is claimed is:
 1. A substantive coating for dental tape whereinsaid coating: contains a crystal control substance is saliva soluble issubstantially crystal-free comprises from between about 20% and about120% by weight of said tape has a flake value of less than about 20 anda release value of about 90 to
 100. 2. A substantive coating for dentaltape according to claim 1, wherein said crystal control substance isselected from the group consisting of long chain fatty alcohols ormixtures thereof and liquid surfactants having the standard formula:

wherein R₁ to R₄ represent H or aliphatic acyl groups having from 10 to30 carbon atoms.
 3. A substantive coating for dental tape according toclaim 2, containing an active, chemotherapeutic ingredient selected fromthe group consisting of stannous fluoride, potassium nitrate, triclosan,chlorhexidine, cetylpyridinium chloride, domaphen bromide,metronidazole, doxycycline, aspirin and mixtures thereof.
 4. A methodfor treating interproximal and subgingival sites in the oral cavitycomprising flossing said sites with a coated monofilament dental tapehaving a substantive coating, wherein said coating: contains a crystalcontrol substance, is saliva soluble, is substantially crystal-free,comprises from between about 20% and about 120% by weight of said tape,and has a flake value of less than about 20 and a release value of about90 to
 100. 5. A method for treating interproximal and subgingival sitesin the oral cavity according to claim 4, wherein said coating containsan active ingredient selected from the group consisting of stannousfluoride, potassium nitrate, triclosan, chlorhexidine, cetylpyridiniumchloride, domaphen bromide, metronidazole, doxycycline, aspirin, othernon-steroidal anti-inflammatory drugs and mixtures thereof.
 6. A methodfor treating interproximal and subgingival sites in the oral cavityaccording to claim 4, for the purposes of mitigating, curing orotherwise affecting systemic diseases which are caused or exacerbated bypoor oral health such as heart disease, diabetes, tobacco-use relateddisease, low-birth weight babies, immuno-compromized patients, whereinsaid coating contains an active ingredient selected from the groupconsisting of stannous fluoride, potassium nitrate, triclosan,chlorhexidine, cetyl-pyridinium chloride, domaphen bromide,metronidazole, doxycycline, aspirin, other non-steroidalanti-inflammatory drugs (NSAIDS) and mixtures thereof.
 7. A method forphysically removing subgingival biofilms from interproximal andsubgingival sites in the oral cavity comprising flossing said sites witha coated monofilament dental tape having a substantive coating, whereinsaid coating: contains a crystal control substance is saliva soluble issubstantially crystal-free comprises from between about 20% and about120% by weight of said tape has a flake value of less than about 20 anda release value of about 90 to
 100. 8. A method for manufacturing acoated monofilament dental tape containing a substantive coating that:contains a crystal control substance is saliva soluble is substantiallycrystal-free comprises from between about 20% and about 120% by weightof said tape has a flake value of less than about 20 and a release valueof about 90 to 100, said method comprising the steps of: a. introducingsaid tape to a loading means containing said coating which is fluid andmaintained substantially uniform, while being held at a temperatureabove the melting temperature of said coating; b. removing excesscoating from said tape by doctoring or calendering said excess coatingoff said coated tape after coating, and c. cooling said coated tape andwinding the same onto master spools prior to bobbin winding.
 9. Asubstantive coating for dental tape according to claim 2, wherein thedental tape is a monofilament tape selected from the group consisting ofPTFE, non-PTFE, elastomeric, polycomponent and other polymermonofilament flosses and mixtures thereof.